Be prepared.
Tasers, mace, pepper spray, all come in second in a gun fight. Bad guys carry guns most of the time. Bad guys who are on meth, coke, and other drugs are sometimes difficult to overpower with chemicals. 12 ga. #4 shot works best.
No normal person wants to kill another person, but if it comes down to the low life pond scum bad guy, or your wife and child, which do you choose?
Most of us will never have to make this decision, but everyone should be mentally prepared to use what ever is needed to protect your loved ones.
Mossberg makes a 12 Ga. pump shotgun that comes with both long and short barrels that are removable, that goes for around $225 at Big 5 Sports stores. Like an earlier post stated, sometimes just jacking a shell into the chamber will scare a would be attacker away. In my law enforcement days, I have seen people willing to rush a person who is holding a .22 cal. hand gun, but I have never met a person willing to rush a person holding a 12 ga. shotgun.
God willing, you will never need to use it.